FAIR VALUE MEASUREMENTS - Fair Value Hierarchy Levels of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Assets:
Available-for-sale Securities	$ 69,907	$ 68,270
Asset derivatives	706	802
Other Investments	179	171
Cash and cash equivalents	4,363	4,658
Total assets	75,155	73,901
Liabilities:
Liability derivatives	599	2,423
Total liabilities	599	2,423
Foreign currency swaps
Assets:
Asset derivatives	637	746
Liabilities:
Liability derivatives	393	318
Foreign currency forwards
Assets:
Asset derivatives	64	56
Liabilities:
Liability derivatives	165	1,912
Foreign currency options
Liabilities:
Liability derivatives	15	33
Credit default swaps
Assets:
Asset derivatives	1
Interest rate swaps
Assets:
Asset derivatives	4
Interest rate swaptions
Liabilities:
Liability derivatives	26	160
Fixed Maturities
Assets:
Available-for-sale Securities	67,319	65,573
Fixed Maturities | Government and Agencies Debt Securities
Assets:
Available-for-sale Securities	18,856	19,198
Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	1,260	1,257
Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	621	602
Fixed Maturities | Public Utilities
Assets:
Available-for-sale Securities	8,218	7,897
Fixed Maturities | Sovereign and supranational
Assets:
Available-for-sale Securities	1,468	1,416
Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	6,655	6,598
Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities	30,241	28,605
Perpetual securities
Assets:
Available-for-sale Securities	2,560	2,669
Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	2,341	2,438
Perpetual securities | Other corporate
Assets:
Available-for-sale Securities	219	231
Equity securities
Assets:
Available-for-sale Securities	28	28
Level 1
Assets:
Available-for-sale Securities	18,380	18,702
Asset derivatives	0	0
Other Investments	179	171
Cash and cash equivalents	4,363	4,658
Total assets	22,922	23,531
Liabilities:
Total liabilities	0	0
Level 1 | Foreign currency swaps
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 1 | Foreign currency forwards
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 1 | Foreign currency options
Liabilities:
Liability derivatives	0	0
Level 1 | Credit default swaps
Assets:
Asset derivatives	0
Level 1 | Interest rate swaps
Assets:
Asset derivatives	0
Level 1 | Interest rate swaptions
Liabilities:
Liability derivatives	0	0
Level 1 | Fixed Maturities
Assets:
Available-for-sale Securities	18,361	18,683
Level 1 | Fixed Maturities | Government and Agencies Debt Securities
Assets:
Available-for-sale Securities	18,361	18,683
Level 1 | Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Public Utilities
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Sovereign and supranational
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	0	0
Level 1 | Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities	0	0
Level 1 | Perpetual securities
Assets:
Available-for-sale Securities	0	0
Level 1 | Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	0	0
Level 1 | Perpetual securities | Other corporate
Assets:
Available-for-sale Securities	0	0
Level 1 | Equity securities
Assets:
Available-for-sale Securities	19	19
Level 2
Assets:
Available-for-sale Securities	51,127	49,167
Asset derivatives	596	696
Other Investments	0	0
Cash and cash equivalents	0	0
Total assets	51,723	49,863
Liabilities:
Total liabilities	207	2,105
Level 2 | Foreign currency swaps
Assets:
Asset derivatives	528	640
Liabilities:
Liability derivatives	1	0
Level 2 | Foreign currency forwards
Assets:
Asset derivatives	64	56
Liabilities:
Liability derivatives	165	1,912
Level 2 | Foreign currency options
Liabilities:
Liability derivatives	15	33
Level 2 | Credit default swaps
Assets:
Asset derivatives	0
Level 2 | Interest rate swaps
Assets:
Asset derivatives	4
Level 2 | Interest rate swaptions
Liabilities:
Liability derivatives	26	160
Level 2 | Fixed Maturities
Assets:
Available-for-sale Securities	48,711	46,641
Level 2 | Fixed Maturities | Government and Agencies Debt Securities
Assets:
Available-for-sale Securities	495	515
Level 2 | Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	1,260	1,257
Level 2 | Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	400	379
Level 2 | Fixed Maturities | Public Utilities
Assets:
Available-for-sale Securities	8,218	7,897
Level 2 | Fixed Maturities | Sovereign and supranational
Assets:
Available-for-sale Securities	1,468	1,416
Level 2 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	6,629	6,572
Level 2 | Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities	30,241	28,605
Level 2 | Perpetual securities
Assets:
Available-for-sale Securities	2,410	2,520
Level 2 | Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	2,191	2,289
Level 2 | Perpetual securities | Other corporate
Assets:
Available-for-sale Securities	219	231
Level 2 | Equity securities
Assets:
Available-for-sale Securities	6	6
Level 3
Assets:
Available-for-sale Securities	400	401
Asset derivatives	110	106
Other Investments	0	0
Cash and cash equivalents	0	0
Total assets	510	507
Liabilities:
Total liabilities	392	318
Level 3 | Foreign currency swaps
Assets:
Asset derivatives	109	106
Liabilities:
Liability derivatives	392	318
Level 3 | Foreign currency forwards
Assets:
Asset derivatives	0	0
Liabilities:
Liability derivatives	0	0
Level 3 | Foreign currency options
Liabilities:
Liability derivatives	0	0
Level 3 | Credit default swaps
Assets:
Asset derivatives	1
Level 3 | Interest rate swaps
Assets:
Asset derivatives	0
Level 3 | Interest rate swaptions
Liabilities:
Liability derivatives	0	0
Level 3 | Fixed Maturities
Assets:
Available-for-sale Securities	247	249
Level 3 | Fixed Maturities | Government and Agencies Debt Securities
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Municipalities
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Mortgage- and asset-backed securities
Assets:
Available-for-sale Securities	221	223
Level 3 | Fixed Maturities | Public Utilities
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Sovereign and supranational
Assets:
Available-for-sale Securities	0	0
Level 3 | Fixed Maturities | Banks/financial Institutions
Assets:
Available-for-sale Securities	26	26
Level 3 | Fixed Maturities | Other corporate
Assets:
Available-for-sale Securities	0	0
Level 3 | Perpetual securities
Assets:
Available-for-sale Securities	150	149
Level 3 | Perpetual securities | Banks/financial Institutions
Assets:
Available-for-sale Securities	150	149
Level 3 | Perpetual securities | Other corporate
Assets:
Available-for-sale Securities	0	0
Level 3 | Equity securities
Assets:
Available-for-sale Securities	3	3
Variable Interest Entity, Consolidated
Assets:
Asset derivatives	110	106
Total assets	5,292	4,785
Liabilities:
Liability derivatives	392	318
Total liabilities	$ 392	$ 318